You should choose an adapter whose guide matches your computer's operating system. For example, if you are running a Windows XP, buy a Belkin F5D7050. You will realize that many adapters are compatible on the same operating system: just go for the one whose guide is the clearest for you.

Be aware that an adapter costs around 15 dollars in average; the cheapest being TendaUsb which is 12 dollars. They are all identical in terms of quality: a Belkin is as efficient as a Planex even if it is not an official adapter.

Planex adapters, provided by PCI, are the official ones which means they have been optimized especially for Xlinkkai. Note that they are not available in shops: you have to buy them through the Internet. May you find here some famous selling websites where they are available, depending on the part of the world where you live.

Wifi Max have been associated with the name of Xlinkkai for ages: it was reported to be the only one adapter compatible with the software. Nowadays, this assessment is not true: Wifi max does not monopolize Kai's compatibility any longer. They are hard to be found through Internet's selling websites while barely impossible in standard shops except in some countries like Singapore. Here is a short discussion about that matter if you are any interested: http://www.teamxlink.co.uk/forum/viewtopic.php?t=35552

Various Wifi's firms (Belkin, Dlink, TP link among some others) had included the Psp Xlink Mode as a plugin in most of their adapters. Their advantage is they easily can be found in shops. Moreover, some firms like TP Link, reported their wifi cards which have that plugin into their websites.